MAMIRAUÁ RESERVE, Brazil — On this stretch of the Amazon River, you don't need a fish finder to locate the pirarucu, one of the world's largest freshwater fish. The splashing gives them away.

Photograph by Andre Dib The largest scaled freshwater fish in the world ... his work to other parts of the Brazilian Amazon as well as the Ucayali River in Peru, another major tributary of ...

SAO RAIMUNDO, Brazil - Even in the most biodiverse rainforest of the world, the pirarucu stands out: It can weigh up to 440 pounds, by far the largest of 2,300 known fish species in the Amazon.

Prepare to be amazed by the 100 biggest river monsters ever captured on camera! From massive catfish and giant alligator gars ...

Now a big fish story - seriously ... (SOUNDBITE OF WATER SWOOSHING) JOHN OTIS, BYLINE: Here along the Amazon River in northern Brazil, you don't need a fish finder to locate the pirarucu.

Reaching up to 10 feet (3 meters) long and weighing 440 pounds (200 kilograms), arapaima are the largest freshwater fish in South America—and an important species in the Amazon River ecosystem.

It helped the Amazon’s largest fish escape risk of extinction and is ... Unlike other aquatic species of the Amazon, such as river dolphins, the pirarucu — also known as arapaima ...

It helped the Amazon's largest fish escape risk of extinction and is ... Unlike other aquatic species of the Amazon, such as river dolphins, the pirarucu — also known as arapaima ...

The rich organic matter that gives the largest tributary of the Amazon River, the Rio Negro, its characteristic black hue may provide fish with some protection from the negative effects of copper ...

Image A parched section of the Solimões River, one of the largest tributaries of the Amazon, last month.Credit...Jorge Silva/Reuters By stirring up riverbeds, fish and other aquatic life would be ...